In this article we will show you the solution of difference between find and index in python, both of these methods are used to search for a particular substring within a larger string, but they have some essential differences that are important to understand.

We will go over the syntax and functionality of both methods and provide examples to illustrate their usage.

To understand the differences between find() and index(), we will first explain what they do and how they are used.

Then, we will provide code examples to show how these methods work in practice.

The find() method is used to search for a substring within a larger string and returns the lowest index of the first occurrence of the substring.

If the substring cannot be found, the function returns -1. The syntax for the find() method is as follows:

string.find(substring, start, end)

Here, the string is the string in which we want to search for the substring, the substring is the substring we want to find, and the start and end are optional parameters that specify the starting and ending indices of the search.

If start and end are not provided, the search will start from the beginning of the string and continue to the end.

Step By Step Guide On Difference Between Find And Index In Python :-

Example 1

string = "Hello, world!"
substring = "world"
# Using find()
print(string.find(substring)) # Output: 7
# Using index()
print(string.index(substring)) # Output: 7

1. The program starts by declaring two variables, a string, and a substring. The string variable is set to the string "Hello, world!", with "world" as the substring variable.
2. The program then prints the output of the find() method on the string and substring variables. The find() method looks for the substring within the string and returns the index of the first character of the substring if found.
3. The program then prints the output of the index() method on the same variables. The index() method works the same way as the find the () method, but it will raise an error if the substring is not found.
4. In this case, both the find() and index() methods return the same value (7), since the substring "world" can be found in the string "Hello, world!" at index 7.

Example 2

string = "Hello, world!"
substring = "Python"
# Using find()
print(string.find(substring)) # Output: -1
# Using index()
print(string.index(substring)) # Output: ValueError: substring not found

1. We start by setting two variables, string, and substring.
2. "Hello, world!" is set as the string variable, and "Python" is set as the substring variable.
3. We then use the find() method to check if the substring is present in the string.
4. The find() method will return -1 if the substring is not present in the string.
5. We then use the index() method to check if the substring is present in the string.
6. The index() method will throw a ValueError if the substring is not present in the string.
7. Finally, we print the results of the find() and index() methods.

Conclusion :-

In conclusion, the find() and index() functions in Python are very similar in that they both search for a substring in a string and return the index of the first occurrence of the substring.

However, there are some differences between these functions that we have discussed in this tutorial.

The find() function returns -1 if the substring is not found, while the index() function raises a ValueError with the message "substring not found".

This makes the find() function more forgiving when searching for a substring that may or may not exist in a string.

Additionally, the find() function can take an optional second argument to specify the starting index of the search, while the index() function only searches from the beginning of the string.

I hope this article on difference between find and index in python helps you and the steps and method mentioned above are easy to follow and implement.